Some items from this specific schematic: Gasket(12.1x16.2x3.7) (nas), Gasket(5.8x13x1.8) (nas), Lock Washer, Washer.
The most reasonably priced component used on the Dr600s 1989 (k) (e02 E04 E15 E16 E17 E18 E21 E22 E25 E34 E39 E53 Muffler (model F) is the Washer,lock.
In this schematic the "Gasket" is used most often.